TAPS Working Group T. Pauly, Ed.
Internet-Draft Apple Inc.
Intended status: Informational B. Trammell, Ed.
Expires: November 1, 2018 ETH Zurich
A. Brunstrom
Karlstad University
G. Fairhurst
University of Aberdeen
C. Perkins
University of Glasgow
P. Tiesel
TU Berlin
C. Wood
Apple Inc.
April 30, 2018
An Architecture for Transport Services
draft-ietf-taps-arch-00
Abstract
This document provides an overview of the architecture of Transport
Services, a system for exposing the features of transport protocols
to applications. This architecture serves as a basis for Application
Programming Interfaces (APIs) and implementations that provide
flexible transport networking services. It defines the common set of
terminology and concepts to be used in more detailed discussion of
Transport Services.
Status of This Memo
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provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
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Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on November 1, 2018.
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Copyright Notice
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document authors. All rights reserved.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Background . . . . . . . . . . . . . . . . . . . . . . . . . 3
3. Design Principles . . . . . . . . . . . . . . . . . . . . . . 4
3.1. Common APIs for Common Features . . . . . . . . . . . . . 4
3.2. Access to Specialized Features . . . . . . . . . . . . . 4
3.3. Scope for API and Implementation Definitions . . . . . . 5
4. Transport Services Architecture and Concepts . . . . . . . . 6
4.1. Transport Services API Concepts . . . . . . . . . . . . . 7
4.1.1. Basic Objects . . . . . . . . . . . . . . . . . . . . 9
4.1.2. Pre-Establishment . . . . . . . . . . . . . . . . . . 10
4.1.3. Establishment Actions . . . . . . . . . . . . . . . . 11
4.1.4. Data Transfer Objects and Actions . . . . . . . . . . 11
4.1.5. Event Handling . . . . . . . . . . . . . . . . . . . 12
4.1.6. Termination Actions . . . . . . . . . . . . . . . . . 13
4.2. Transport System Implementation Concepts . . . . . . . . 13
4.2.1. Gathering . . . . . . . . . . . . . . . . . . . . . . 14
4.2.2. Racing . . . . . . . . . . . . . . . . . . . . . . . 14
4.2.3. Message Framing, Parsing, and Serialization . . . . . 14
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 15
6. Security Considerations . . . . . . . . . . . . . . . . . . . 16
7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 16
8. Informative References . . . . . . . . . . . . . . . . . . . 16
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 17
1. Introduction
Many APIs to perform transport networking have been deployed, perhaps
the most widely known and imitated being the BSD socket() interface.
The names and functions between these APIs are not consistent, and
vary depending on the protocol being used. For example, sending and
receiving on a stream of data is conceptually the same between
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operating on an unencrypted Transmission Control Protocol (TCP)
stream and operating on an encrypted Transport Layer Security (TLS)
[I-D.ietf-tls-tls13] stream over TCP, but applications cannot use the
same socket send() and recv() calls on top of both kinds of
connections. Similarly, terminology for the implementation of
protocols offering transport services vary based on the context of
the protocols themselves. This variety can lead to confusion when
trying to understand the similarities and differences between
protocols, and how applications can use them effectively.
The goal of the Transport Services architecture is to provide a
common, flexible, and reusable interface for transport protocols. As
applications adopt this interface, they will benefit from a wide set
of transport features that can evolve over time, and ensure that the
system providing the interface can optimize its behavior based on the
application requirements and network conditions.
This document is developed in parallel with the specification of the
Transport Services API [I-D.trammell-taps-interface] and
Implementation [draft-brunstrom-taps-impl] documents.
2. Background
The Transport Services architecture is based on the survey of
Services Provided by IETF Transport Protocols and Congestion Control
Mechanisms [RFC8095], and the distilled minimal set of the features
offered by transport protocols [I-D.ietf-taps-minset]. This work has
identified common features and patterns across all transport
protocols developed thus far in the IETF.
Since transport security is an increasingly relevant aspect of using
transport protocols on the Internet, this architecture also considers
the impact of transport security protocols on the feature set exposed
by transport services [I-D.pauly-taps-transport-security].
One of the key insights to come from identifying the minimal set of
features provided by transport protocols [I-D.ietf-taps-minset] was
that features either require application interaction and guidance
(referred to as Functional Features), or else can be handled
automatically by a system implementing Transport Services (referred
to as Automatable Features). Among the Functional Features, some
were common across all or nearly all transport protocols, while
others could be seen as features that, if specified, would only be
useful with a subset of protocols, or perhaps even a single transport
protocol, but would not harm the functionality of other protocols.
For example, some protocols can deliver messages faster for
applications that do not require them to arrive in the order in which
they were sent. However, this functionality must be explicitly
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allowed by the application, since reordering messages would be
undesirable in many cases.
3. Design Principles
The goal of the Transport Services architecture is to redefine the
interface between applications and transports in a way that allows
the transport layer to evolve and improve without fundamentally
changing the contract with the application. This requires a careful
consideration of how to expose the capabilities of protocols.
There are several degrees in which a Transport Services system can
offer flexibility to an application: it can provide access to
multiple sets of protocols and protocol features, it can use these
protocols across multiple paths that may have different performance
and functional characteristics, and it can communicate with different
Remote Endpoints to optimize performance. Beyond these, if the API
for the system remains the same over time, new protocols and features
may be added to the system's implementation without requiring changes
in applications for adoption.
The following considerations were used in the design of this
architecture.
3.1. Common APIs for Common Features
Functionality that is common across multiple transport protocols
should be accessible through a unified set of API calls. An
application should be able to implement logic for its basic use of
transport networking (establishing the transport, and sending and
receiving data) once, and expect that implementation to continue to
function as the transports change.
Any Transport Services API must allow access to the distilled minimal
set of features offered by transport protocols
[I-D.ietf-taps-minset].
3.2. Access to Specialized Features
Since applications will often need to control fine-grained details of
transport protocols to optimize their behavior and ensure
compatibility with remote peers, a Transport Services system also
needs to allow more specialized protocol features to be used. The
interface for these specialized options should be exposed differently
from the common options to ensure flexibility.
A specialized feature may be required by an application only when
using a specific protocol, and not when using others. For example,
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if an application is using UDP, it may require control over the
checksum or fragmentation behavior for UDP; if it used a protocol to
frame its data over a byte stream like TCP, it would not need these
options. In such cases, the API should expose the features in such a
way that they take effect when a particular protocol is selected, but
do not imply that only that protocol may be used if there are
equivalent options.
Other specialized features, however, may be strictly required by an
application and thus constrain the set of protocols that can be used.
For example, if an application requires encryption of its transport
data, only protocol stacks that include some transport security
protocol are eligible to be used. A Transport Services API must
allow applications to define such requirements and constrain the
system's options. Since such options are not part of the core/common
features, it should be simple for an application to modify its set of
constraints and change the set of allowable protocol features without
changing the core implementation.
3.3. Scope for API and Implementation Definitions
The Transport Services API is envisioned as the abstract model for a
family of APIs that share a common way to expose transport features
and encourage flexibility. The abstract API definition
[I-D.trammell-taps-interface] describes this interface and is aimed
at application developers.
Implementations that provide the Transport Services API
[draft-brunstrom-taps-impl] will vary due to system-specific support
and the needs of the deployment scenario. It is expected that all
implementations of Transport Services will offer the entire mandatory
API, but that some features will not be functional in certain
implementations. All implementations must offer sufficient APIs to
use the distilled minimal set of features offered by transport
protocols [I-D.ietf-taps-minset], including API support for TCP and
UDP transport, but it is possible that some very constrained devices
might not have, for example, a full TCP implementation.
In order to preserve flexibility and compatibility with future
protocols, top-level features in the Transport Services API should
avoid referencing particular transport protocols. Mappings of these
API features in the Implementation document, on the other hand, must
explain the ramifications of each feature on existing protocols. It
is expected that the Implementation document will be updated and
supplemented as new protocols and protocol features are developed.
It is important to note that neither the Transport Services API nor
the Implementation document defines new protocols that require any
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changes on remote hosts. The Transport Services system must be
deployable on one side only, as a way to allow an application to make
better use of available capabilities on a system and protocol
features that may be supported by peers across the network.
4. Transport Services Architecture and Concepts
The concepts defined in this document are intended primarily for use
in the documents and specifications that describe the Transport
Services architecture and API. While the specific terminology may be
used in some implementations, it is expected that there will remain a
variety of terms used by running code.
The architecture divides the concepts for Transport Services into two
categories:
1. API concepts, which are meant to be exposed to applications; and
2. System-implementation concepts, which are meant to be internally
used when building systems that implement Transport Services.
The following diagram summarizes the top-level concepts in the
architecture and how they relate to one another.
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+------------------------------------------------------+
| Application |
+-+----------------+------^-------+--------^-----------+
| | | | |
pre- | data | events
establishment | transfer | |
| establishment | termination |
| | | | |
| +--v------v-------v+ |
+-v-------------+ Basic Objects +-------+----------+
| Transport +--------+---------+ |
| Services | |
| API | |
+------------------------|----------------------------+
|
+------------------------|----------------------------+
| Transport | |
| System | +-----------------+ |
| Implementation | | Cached | |
| | | State | |
| (Candidate Gathering) | +-----------------+ |
| | |
| (Candidate Racing) | +-----------------+ |
| | | System | |
| | | Policy | |
| +----------v-----+ +-----------------+ |
| | Protocol | |
+-------------+ Stack(s) +----------------------+
+-------+--------+
V
Network Layer Interface
Figure 1: Concepts and Relationships in the Transport Services
Architecture
4.1. Transport Services API Concepts
Fundamentally, a Transport Services API needs to provide basic
objects (Section 4.1.1) that allow applications to establish
communication and send and receive data. These may be exposed as
handles or referenced objects, depending on the language.
Beyond the basic objects, there are several high-level groups of
actions that any Transport Services API must provide:
o Pre-Establishment (Section 4.1.2) encompasses the properties that
an application can pass to describe its intent, requirements,
prohibitions, and preferences for its networking operations. For
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any system that provides generic Transport Services, these
properties should primarily offer knobs that are applicable to
multiple transports. Properties may have a large impact on the
rest of the aspects of the interface: they can modify how
establishment occurs, they can influence the expectations around
data transfer, and they determine the set of events that will be
supported.
o Establishment (Section 4.1.3) focuses on the actions that an
application takes on the basic objects to prepare for data
transfer.
o Data Transfer (Section 4.1.4) consists of how an application
represents data to be sent and received, the functions required to
send and receive that data, and how the application is notified of
the status of its data transfer.
o Event Handling (Section 4.1.5) defines the set of properties about
which an application can receive notifications during the lifetime
of transport objects. Events can also provide opportunities for
the application to interact with the underlying transport by
querying state or updating maintenance options.
o Termination (Section 4.1.6) focuses on the methods by which data
transmission is ceased, and state is torn down in the transport.
The diagram below provides a high-level view of the actions taken
during the lifetime of a connection.
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Pre-Establishment : Established : Termination
----------------- : ----------- : -----------
: Close() :
+---------------+ Initiate() +------------+ Abort() :
+-->| Preconnection |----------->| Connection |---------------> Closed
| +---------------+ : +------------+ Connection:
| : ^ ^ | Finished :
+-- Local Endpoint : | | | :
| : | | +---------+ :
+-- Remote Endpoint : | | | :
| : | |Send() | :
+-- Path Selection : | +---------+ v :
| Properties : | | Message | Message :
| : | | to send | Received :
+-- Protocol Selection : | +---------+ :
| Properties : | :
| : | :
+-- Specific Protocol : | :
| Properties : | :
| : | :
| +----------+ : | :
+-->| Listener |-----------------+ :
+----------+ Connection Received :
^ : :
| : :
Listen() : :
Figure 2: The lifetime of a connection
4.1.1. Basic Objects
o Preconnection: A Preconnection object is a representation of a
potential connection. It has state that describes parameters of a
Connection that might exist in the future: the Local Endpoint from
which that Connection will be established, the Remote Endpoint to
which it will connect, and Path Selection Properties, Protocol
Selection Properties, and Specific Protocol Properties that
influence the choice of transport that a Connection will use. A
Preconnection can be fully specified and represent a single
possible Connection, or it can be partially specified such that it
represents a family of possible Connections. The Local Endpoint
must be specified if the Preconnection is used to Listen for
incoming connections, but is optional if it is used to Initiate
connections. The Remote Endpoint must be specified in the
Preconnection is used to Initiate connections, but is optional if
it is used to Listen for incoming connections. The Local Endpoint
and the Remote Endpoint must both be specified if a peer-to-peer
Rendezvous is to occur based on the Preconnection.
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o Connection: A Connection object represents an active transport
protocol instance that can send and/or receive Messages between a
Local Endpoint and a Remote Endpoint. It holds state pertaining
to the underlying transport protocol instance and any ongoing data
transfer. This represents, for example, an active connection in a
connection-oriented protocol such as TCP, or a fully-specified
5-tuple for a connectionless protocol such as UDP.
o Listener: A Listener object accepts incoming transport protocol
connections from Remote Endpoints and generates corresponding
Connection objects. It is created from a Preconnection object
that specifies the type of incoming connections it will accept.
4.1.2. Pre-Establishment
o Endpoint: An Endpoint represents one side of a transport
connection. Endpoints can be Local Endpoints or Remote Endpoints,
and respectively represent an identity that the application uses
for the source or destination of a connection. Endpoint can vary
in levels of specificity, and can be resolved to more concrete
identities.
o Remote Endpoint: The Remote Endpoint represents the application's
name for a peer that can participate in a transport connection.
For example, the combination of a DNS name for the peer and a
service name/port.
o Local Endpoint: The Local Endpoint represents the application's
name for itself that it wants to use for transport connections.
For example, a local IP address and port.
o Path Selection Properties: The Path Selection Properties consist
of the options that an application may set to influence the
selection of paths between itself and the Remote Endpoint. These
options can come in the form of requirements, prohibitions, or
preferences. Examples of options which may influence path
selection include the interface type (such as a Wi-Fi Ethernet
connection, or a Cellular LTE connection), characteristics of the
path that are locally known like Maximum Transmission Unit (MTU)
or discovered like Path MTU (PMTU), or predicted based on cached
information like expected throughput or latency.
o Protocol Selection Properties: The Protocol Selection Properties
consist of the options that an application may set to influence
the selection of transport protocol, or to configure the behavior
of generic transport protocol features. These options come in the
form of requirements, prohibitions, and preferences. Examples
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include reliability, service class, multipath support, and fast
open support.
o Specific Protocol Properties: The Specific Protocol Properties
refer to the subset of Protocol Properties options that apply to a
single protocol (transport protocol, IP, or security protocol).
The presence of such Properties does not necessarily require that
a specific protocol must be used when a Connection is established,
but that if this protocol is employed, a particular set of options
should be used.
4.1.3. Establishment Actions
o Initiate is the primary action that an application can take to
create a Connection to a remote endpoint, and prepare any required
local or remote state to be able to send and/or receive Messages.
For some protocols, this may initiate a client-to-server style
handshake; for other protocols, this may just establish local
state. The process of identifying options for connecting, such as
resolution of the Remote Endpoint, occurs in response the Initiate
call.
o Listen is the action of marking a Listener as willing to accept
incoming Connections. The Listener will then create Connection
objects as incoming connections are accepted (Section 4.1.5).
o Rendezvous is the action of establishing a peer-to-peer connection
with a remote endpoint. It simultaneously attempts to initiate a
connection to a remote endpoint whilst listening for an incoming
connection from that endpoint. This corresponds, for example, to
a TCP simultaneous open. The process of identifying options for
the connection, such as resolution of the Remote Endpoint, occurs
during the Rendezvous call. If successful, the rendezvous call
returns a Connection object to represent the established peer-to-
peer connection.
4.1.4. Data Transfer Objects and Actions
o Message: A Message object is a unit of data that can be
represented as bytes that can be transferred between two endpoints
over a transport connection. The bytes within a Message are
assumed to be ordered within the Message. If an application does
not care about the order in which a peer receives two distinct
spans of bytes, those spans of bytes are considered independent
Messages. Messages may or may not be usable if incomplete or
corrupted. Boundaries of a Message may or may not be understood
or transmitted by transport protocols. Specifically, what one
application considers to be two Messages sent on a stream-based
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transport may be treated as a single Message by the application on
the other side.
o Send is the action to transmit a Message or partial Message over a
Connection to a Remote Endpoint. The interface to Send may
include options specific to how the Message's content is to be
sent. Status of the Send operation may be delivered back to the
application in an event (Section 4.1.5).
o Receive is an action that indicates that the application is ready
to asynchronously accept a Message over a Connection from a Remote
Endpoint, while the Message content itself will be delivered in an
event (Section 4.1.5). The interface to Receive may include
options specific to the Message that is to be delivered to the
application.
4.1.5. Event Handling
This list of events that can be delivered to an application is not
exhaustive, but gives the top-level categories of events. The API
may expand this list.
o Connection Ready: Signals to an application that a given
Connection is ready to send and/or receive Messages. If the
Connection relies on handshakes to establish state between peers,
then it is assumed that these steps have been taken.
o Connection Finished: Signals to an application that a given
Connection is no longer usable for sending or receiving Messages.
This should deliver an error to the application that describes the
nature of the termination.
o Connection Received: Signals to an application that a given
Listener has passively received a Connection.
o Message Received: Delivers received Message content to the
application, based on a Receive action. This may include an error
if the Receive action cannot be satisfied due to the Connection
being closed.
o Message Sent: Notifies the application of the status of its Send
action. This may be an error if the Message cannot be sent, or an
indication that Message has been processed by the protocol stack.
o Path Properties Changed: Notifies the application that some
property of the Connection has changed that may influence how and
where data is sent and/or received.
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4.1.6. Termination Actions
o Close is the action an application may take on a Connection to
indicate that it no longer intends to send data, is no longer
willing to receive data, and that the protocol should signal this
state to the remote endpoint if applicable.
o Abort is an action the application may take on a Connection to
indicate a Close, but with the additional indication that the
transport system should not attempt to deliver any outstanding
data.
4.2. Transport System Implementation Concepts
The Transport System Implementation Concepts define the set of
objects used internally to a system or library to provide the
functionality of transport networking, as required by the abstract
interface.
o Connection Group: A Connections Group is a set of Connections that
share properties. For multiplexing transport protocols, the
Connection Group defines the set of Connections that can be
multiplexed together.
o Path: A Path represents an available set of properties of a
network route on which packets may be sent or received.
o Protocol Instance: A Protocol Instance is a single instance of one
protocol, including any state it has necessary to establish
connectivity or send and receive Messages.
o Protocol Stack: A Protocol Stack is a set of Protocol Instances
(including relevant application, security, transport, or Internet
protocols) that are used together to establish connectivity or
send and receive Messages. A single stack may be simple (a single
transport protocol instance over IP), or complex (multiple
application protocol streams going through a single security and
transport protocol, over IP; or, a multi-path transport protocol
over multiple transport sub-flows).
o System Policy: System Policy represents the input from an
operating system or other global preferences that can constrain or
influence how an implementation will gather candidate paths and
protocols (Section 4.2.1) and race the candidates during
establishment (Section 4.2.2). Specific aspects of the System
Policy may apply to all Connections, or only certain ones
depending on the runtime context and properties of the Connection.
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o Cached State: Cached State is the state and history that the
implementation keeps for each set of associated endpoints that
have been used previously. This can include DNS results, TLS
session state, previous success and quality of transport protocols
over certain paths.
4.2.1. Gathering
o Path Selection: Path Selection represents the act of choosing one
or more paths that are available to use based on the Path
Selection Properties provided by the application, and a Transport
Services system's policies and heuristics.
o Protocol Selection: Protocol Selection represents the act of
choosing one or more sets of protocol options that are available
to use based on the Protocol Properties provided by the
application, and a Transport Services system's policies and
heuristics.
4.2.2. Racing
o Protocol Option Racing: Protocol Racing is the act of attempting
to establish, or scheduling attempts to establish, multiple
Protocol Stacks that differ based on the composition of protocols
or the options used for protocols.
o Path Racing: Path Racing is the act of attempting to establish, or
scheduling attempts to establish, multiple Protocol Stacks that
differ based on a selection from the available Paths.
o Endpoint Racing: Endpoint Racing is the act of attempting to
establish, or scheduling attempts to establish, multiple Protocol
Stacks that differ based on the specific representation of the
Remote Endpoint and the Local Endpoint, such as IP addresses
resolved from a DNS hostname.
4.2.3. Message Framing, Parsing, and Serialization
While some transports expose a byte stream abstraction, most higher
level protocols impose some structure onto that byte stream. That
is, the higher level protocol operates in terms of messages, protocol
data units (PDUs), rather than using unstructured sequences of bytes,
with each message being processed in turn. Protocols are specified
in terms of state machines acting on semantic messages, with parsing
the byte stream into messages being a necessary annoyance, rather
than a semantic concern. Accordingly, the Transport Services
architecture exposes messages as the primary abstraction. Protocols
that deal only in byte streams, such as TCP, represent their data in
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each direction as a single, long message. When framing protocols are
placed on top of byte streams, the messages used in the API represent
the framed messages within the stream.
Providing a message-based abstraction also provides:
o the ability to associate deadlines with messages, for transports
that care about timing;
o the ability to provide control of reliability, choosing what
messages to retransmit in the event of packet loss, and how best
to make use of the data that arrived;
o the ability to manage dependencies between messages, when some
messages may not be delivered due to either packet loss or missing
a deadline, in particular the ability to avoid (re-)sending data
that relies on a previous transmission that was never received.
All require explicit message boundaries, and application-level
framing of messages, to be effective. Once a message is passed to
the transport, it can not be cancelled or paused, but prioritization
as well as lifetime and retransmission management will provide the
protocol stack with all needed information to send the messages as
quickly as possible without blocking transmission unnecessarily. The
transport services architecture facilitates this by handling
messages, with known identity (sequence numbers, in the simple case),
lifetimes, niceness, and antecedents.
Transport protocols such as SCTP provide a message-oriented API that
has similar features to those we describe. Other transports, such as
TCP, do not. To support a message oriented API, while still being
compatible with stream-based transport protocols, implementations of
the transport services architecture should provide APIs for framing
and de-framing messages. That is, we push message framing down into
the transport services API, allowing applications to send and receive
complete messages. This is backwards compatible with existing
protocols and APIs, since the wire format of messages does not
change, but gives the protocol stack additional information to allow
it to make better use of modern transport services.
5. IANA Considerations
RFC-EDITOR: Please remove this section before publication.
This document has no actions for IANA.
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6. Security Considerations
The Transport Services architecture does not recommend use of
specific security protocols or algorithms. Its goal is to offer ease
of use for existing protocols by providing a generic security-related
interface. Each provided interface mimics an existing protocol-
specific interface provided by supported security protocols. For
example, trust verification callbacks are common parts of TLS APIs.
Transport Services APIs will expose similar functionality.
Clients must take care to use security APIs appropriately. In cases
where clients use said interface to provide sensitive keying
material, e.g., access to private keys or copies of pre-shared keys
(PSKs), key use must be validated. For example, clients should not
use PSK material created for the Encapsulating Security Protocol
(ESP, part of IPsec) [RFC4303] with QUIC, and clients must not use
private keys intended for server authentication as a keys for client
authentication. Moreover, unlike certain transport features such as
TCP Fast Open (TFO) [RFC7413] or Explicit Congestion Notification
(ECN) [RFC3168] which can fall back to standard configurations,
Transport Services systems must not permit fallback for security
protocols. For example, if a client requests TLS, yet TLS or the
desired version are not available, its connection must fail. Clients
are responsible for implementing protocol or version fallback using a
Transport Services API if so desired.
7. Acknowledgements
This work has received funding from the European Union's Horizon 2020
research and innovation programme under grant agreement No. 644334
(NEAT).
This work has been supported by Leibniz Prize project funds of DFG -
German Research Foundation: Gottfried Wilhelm Leibniz-Preis 2011 (FKZ
FE 570/4-1).
This work has been supported by the UK Engineering and Physical
Sciences Research Council under grant EP/R04144X/1.
Thanks to Stuart Cheshire, Josh Graessley, David Schinazi, and Eric
Kinnear for their implementation and design efforts, including Happy
Eyeballs, that heavily influenced this work.
8. Informative References
[draft-brunstrom-taps-impl]
Anna Brunstrom, . and . Tommy Pauly, "Implementing
Interfaces to Transport Services", n.d..
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[I-D.ietf-taps-minset]
Welzl, M. and S. Gjessing, "A Minimal Set of Transport
Services for TAPS Systems", draft-ietf-taps-minset-03
(work in progress), March 2018.
[I-D.ietf-tls-tls13]
Rescorla, E., "The Transport Layer Security (TLS) Protocol
Version 1.3", draft-ietf-tls-tls13-28 (work in progress),
March 2018.
[I-D.pauly-taps-transport-security]
Pauly, T., Perkins, C., Rose, K., and C. Wood, "A Survey
of Transport Security Protocols", draft-pauly-taps-
transport-security-02 (work in progress), March 2018.
[I-D.trammell-taps-interface]
Trammell, B., Welzl, M., Enghardt, T., Fairhurst, G.,
Kuehlewind, M., Perkins, C., Tiesel, P., and C. Wood, "An
Abstract Application Layer Interface to Transport
Services", draft-trammell-taps-interface-00 (work in
progress), March 2018.
[RFC3168] Ramakrishnan, K., Floyd, S., and D. Black, "The Addition
of Explicit Congestion Notification (ECN) to IP",
RFC 3168, DOI 10.17487/RFC3168, September 2001,
.
[RFC4303] Kent, S., "IP Encapsulating Security Payload (ESP)",
RFC 4303, DOI 10.17487/RFC4303, December 2005,
.
[RFC7413] Cheng, Y., Chu, J., Radhakrishnan, S., and A. Jain, "TCP
Fast Open", RFC 7413, DOI 10.17487/RFC7413, December 2014,
.
[RFC8095] Fairhurst, G., Ed., Trammell, B., Ed., and M. Kuehlewind,
Ed., "Services Provided by IETF Transport Protocols and
Congestion Control Mechanisms", RFC 8095,
DOI 10.17487/RFC8095, March 2017,
.
Authors' Addresses
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Tommy Pauly (editor)
Apple Inc.
One Apple Park Way
Cupertino, California 95014
United States of America
Email: tpauly@apple.com
Brian Trammell (editor)
ETH Zurich
Gloriastrasse 35
8092 Zurich
Switzerland
Email: ietf@trammell.ch
Anna Brunstrom
Karlstad University
Universitetsgatan 2
651 88 Karlstad
Sweden
Email: anna.brunstrom@kau.se
Godred Fairhurst
University of Aberdeen
Fraser Noble Building
Aberdeen, AB24 3UE
Scotland
Email: gorry@erg.abdn.ac.uk
URI: http://www.erg.abdn.ac.uk/
Colin Perkins
University of Glasgow
School of Computing Science
Glasgow G12 8QQ
United Kingdom
Email: csp@csperkins.org
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Philipp S. Tiesel
TU Berlin
Marchstrasse 23
10587 Berlin
Germany
Email: philipp@inet.tu-berlin.de
Chris Wood
Apple Inc.
One Apple Park Way
Cupertino, California 95014
United States of America
Email: cawood@apple.com
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